Add support for sample skewness as defined [here](https://en.wikipedia.org/wiki/Skewness#Sample_skewness). ```js skewness([4, 1, 1, 3]); // -> 0.185185 ``` **Update README.md** under _Averages and measures of central location_ and the table of contents.
Add support for sample skewness as defined here.
Update README.md under Averages and measures of central location and the table of contents.